6. Technical Details

This section provides technical details about the internal implementation of \({\mathcal H}\Phi\).

• 6.1. Hilbert Space Construction
  • 6.1.1. Bit Representation
  • 6.1.2. State Indexing
  • 6.1.3. Symmetry Restrictions
  • 6.1.4. List Arrays
• 6.2. MPI Parallelization
  • 6.2.1. Overview
  • 6.2.2. Site Classification
  • 6.2.3. MPI Communication Patterns
  • 6.2.4. Batched MPI Communication
  • 6.2.5. SpinlessFermion Off-diagonal Two-body Green’s Function
  • 6.2.6. Behavior of MPI-required Tests (ctest)
  • 6.2.7. Fermion Sign
  • 6.2.8. Process Number Requirements
• 6.3. OpenMP Parallelization
  • 6.3.1. Overview
  • 6.3.2. Parallelized Operations
  • 6.3.3. Thread-safe Implementation
  • 6.3.4. Setting the Number of Threads
  • 6.3.5. Performance Considerations
• 6.4. Memory Management
  • 6.4.1. Memory Requirements
  • 6.4.2. Memory Allocation
  • 6.4.3. Estimating Memory Usage
  • 6.4.4. Memory Optimization Strategies
  • 6.4.5. Common Memory Issues
• 6.5. Numerical Precision
  • 6.5.1. Floating-Point Representation
  • 6.5.2. Sources of Numerical Error
  • 6.5.3. Convergence Criteria
  • 6.5.4. Setting Convergence Thresholds
  • 6.5.5. Validation and Testing
  • 6.5.6. Recommendations
• 6.6. Restart Mechanism
  • 6.6.1. Overview
  • 6.6.2. Restart Files
  • 6.6.3. Input/Output Settings
  • 6.6.4. Usage Examples
  • 6.6.5. File Format
  • 6.6.6. MPI Considerations
  • 6.6.7. Common Issues
  • 6.6.8. Best Practices